It’s not his altered ego. His physical body changes form from one to the other. So without a duplicate of himself (say from an alternate universe) the two forms could not actually appear at the same time in-story.

Shaenon can have *both* gerbil and man versions do that cheer, then look at each other in the next panel with either appreciation or apprehension: Probably after solving some reality blindness situation.

Because Mall was hired to assassinate Helen’s mom; they needed someone to stop her. And to infiltrate a villain’s lair, you need a hero; and since there wasn’t one readily available, Helen decided to create one.

I don’t recall his design having anything to do with appealing to anyone except Helen herself. If everything had gone according to plan (yeah, like that ever happens), Mell would never have known who he was, and he would never have had this human form again.

He was designed specifically to stop Mell. Even in this form, that’s sort of like trying to stop a runaway train with a Ford Pinto. There was a distinct likelihood that things were going to blow up spectacularly, and the freight train would keep right on going.

Why does her never knowing who he really was contradict Helen creating him to appeal to Mell? She details pretty sell what her plans for him are here. It certainly sounds like seduction was at least part of what she intended for him.

Yes, appealing to Mell was kind of essential to the mission, but my point still stands. Helen’s design in and of itself was purely selfish. She just chose that particular design because she knew it would also appeal to Mell.